Signaling system for railroads



JuEy 28, 1936. J. BENNETT SIGNALING SYSTEM FOR RAILROADS Filed April 30, 1932 ORI\'IEY Z J ATT Patented July 28, 1 936 PATENT OFFICE SIGNALING SYSTEM FOR RAILROADS Jerry Bennett, Scottsville, N. Y., assignor to General Railway Signal Company, Rochester,

Application April 30, 1932, Seri'aI No. 608,507

19 Claims.

' This invention relates to signal systems for railways, and more particularly tea-signal: system of the three-position polarized control type.

In a polarized control type signaling'systemof the three-position or three-condition type, the control circuit for one signal is pole changed as thesignal next in advance changes from a proceed to a danger position, or vice versa, and

if no special provision is made the control cir-- cuit next in the rear will be momentarily opened when the signal changes from a clear to a caution position or vice versa, and this opening of the control circuit, whichv may cause what is known in signal parlance as a kick-off (which consists of a momentary flash ofa red signal from one signal to the next in the rear along the entire railway system unless there is an intervening' train to break up the control connection between two adjacent signals) is very annoying, and' mayin fact cause an accident due to confusionof the engineer.

In accordance with the present invention it is proposed to provide a stick relay, which maintains the continuity of a control circuit in spite of a clear-to-caution or caution-to-clear change of the signal next in advance. is so controlled that the safety of the system is notimpaired, and further this stick relay serves the additional auxiliary function of afiording ap proach lighting for its associated signal. By'approach lighting is meant the lighting of the signal only during the approach of the train; this relay therefore also serves as an energy saving device.

Other objects, purposes and characteristic features of the present invention will in part be obvious from the accompanying drawing and will in part be more specifically described hereinafter.

' In describing the invention in detail= reference will be made to the accompanying drawing, in which:-- v

"Fig. 1 shows the invention applied to a threeposition search-light type signal;

Figs. 2., 3 and 4 illustrate this search-light-type signal assuming the clear, the caution and the danger position, respectively;

' Fig. 5 shows the invention applied to a threeaspect color light signal controlled by a direct current polar neutral relay; and

Fig. 6 shows'a modified form of the system. shown in Fig. 5. Referring to Fig. L of the drawingv the track rails I: havebeenshowndivided into. blocks by insulating joints 2, of which: the blockv I. and: the;

This stick' relay adjacent ends of the blocks H and J have only been shown. At the entrance endto each block is shown: a search-light type signal, the signal: at the entrance to the block I being designated- S, and the signal at the entrance to the block J be- 5' ing designated S Since the apparatus associated with each of these signals is the same it will suffice to describe only one of these signals, like parts'of the other signals being designated by like reference characters having distinctive ex- 10 ponents. Each of the blocks is provided with the usual track circuit, which for the block I includes the track battery 3, the usual series resistance 4 and the track relay T.

The search-light type signal is one in which a reflector is employed in the rear of the signal. lamp; which reflector causes the reflected light to focus at a point a short distance in front of the. lamp; at a point just beyond this focus the lightis again concentrated by the usual roundel. of the signal. as a result of which a very small multiple color spectacle may be used to filter thev light beam toleave light of a green; yellow or red color for manifesting clear, caution. and. danger respectively. Sincethe color spectacle is. 25. very small and requiresv very little energy for operation, this. spectacle is operated directly by relay mechanism, which has been shown conven-- tionally.

Referring to Figs. 2, 3 and 4 the movable e1e.' ment has been designatedv 5, which is controlled in accordance with the polarity of the direct current in the winding 1 which is normally energized; by direct current of a particular polarity. This: rotor 5, preferably constituting a polar armature, has been shown carrying a spectacle con-- taining a green lens G, a red lens R and a yellow lens; Y,.whichcolor fi-ltersarev located in the focus: of the light. beam when the signal assumes respectively; the clear, the. danger andathe caution position.

'These search-light type signals: contain movablecontacts l0 and l l ,of which the contact Li's under clear position of the signal in engagement.

with thestationary contact I2 but under danger 45..

or caution position in engagement with the stationary contact l3, whereas: the contact Isl: is under caution position in engagement with the stationary contact H. but is under clear and danger conditions. in engagement with the stationary contact Hi, all as clearly shown in Figs. 2', 3 and: 4.. Each of these search-light type signals includes a: lamp L, which is normally extinguished by reason of. the energized condition of the stick relay SR, all. in amanner' more particularly de- 55..

scribed in connection with the operation of the system.

Operation Under normal clear traffic conditions the winding 1 of the signal S is energized through the following circuit:-beginning at the positive terminal of the split battery 2G wire 2 front contact 22 wires 23 and 24 winding of the relay SR wires 25 and 26 contacts l2 and I0 wires 21 and 28, front contact 29 of the track relay T, Wire 30, winding I of the signal S, wires 3|, 32, common return wire C, wires 32 and 33 back to the midpoint of the battery 20 There is also an auxiliary circuit for energizing the winding I of the signal S under normal clear traffic conditions in advance, and this auxiliary circuit is the same as the circuit just traced, except that the stick contact 36 and its associated wires 35 and 31 are substituted for the contact Ni 42 and its associated wires 26 and 2I of the signal S.

It should thus be noted that the stick relay SR is a series--relay, and that it is included in series with the winding I of the signal S next in the rear. Also, it should be noted that operation of the contacts I0 and Il of the'signal S cannotcause deenergization of the winding I of the signal S, because the circuit through the stick contact 36 will remain intact irrespective of the position of the contacts Hi and II of the signal S It may, however, be pointed out at'this time that should the signal S assume the danger position (as shown in Fig. 4) the stick relay SR. would be shunted through the following shunting branch:beginning at the left-hand terminal 24 of the relay SR wire 40 front contact H of the relay SR wire 42 contacts Il -I5 wire 43 contacts I3 --I3 wires 21 and 3i stick contact 36 wire 35 to the other terminal 25 of the stick relay SR Completion of this shunting circuit will not, however, effect deenergiz'ation of relay-SR unless this shunt is maintained for an appreciable period of time, because the relay SR will be rendered slow dropping by reason of having its swindling closed through a circuit of low resistance, so that rapid reversal of the signal from its clear to its caution position or vice versa will not result in dropping the stick relay SR It may be pointed out that this shunting branch circuit has been provided to assure movement of the signal-S to the stop position in the event that a break should occur in the line wire 28 of the signal next in advance, to thus de-energize I and put S .to stop, (block J being assumed unoccupied). forv under this condition the track relay T would be up and therefore the contact 22 would remain closed. If, on the other hand, this safety feature is not desired, this shunting circuit may be omitted, the track relay T and its contacts 29 and 22 being relied upon to manifest occupancy of the block J. I

i Let us now assume that a train is moving in the normal direction of trafilc as indicated by the arrow, in the block H. The presence of this train in the block 1-1 will result in deenergization of the track relay T (not shown) and thereby break the energizing circuit for the stick relay SR, so that this stick relay SR assumes its deenergized position. With the relay SR deenergized the lamp L of the signal S will be illuminated through energization of the following circuit-beginning at the terminal B of a suitable battery, back contact 45 of the relay SR, wire 46, signal lamp L to the other terminal of the same battery. The signal S will thus display a greenlight thereby informing the engineer on the approaching train that traffic conditions in advance are clear.

As this train progresses into the block I it will shunt the track relay T, and thereby cause it to open its contacts 22 and 29, as a result of which the winding I of the signal S is deenergized and the signal S assumes the danger position (see Fig. 4) and displays a red indication because the relay SR is still in its retracted condition with its contact 45 closed. Also, dropping of the contact 29 of the track relay T not only results in deenergizing the winding I of the signal S, but also results in deenergizing the winding of the stick relay SR. at the next signal in advance, so that the lamp L of this signal S is illuminated for reasons already pointed out in connection with the signal S. Furthermore dropping of track relay T by opening of contact 22 prevents closure of a pick-up circuit for relay SR, so that relay SR remains deenergized and lamp L remains energized until thetrain leaves block I to permit picking up of track relay T.

As the train in question now progresses into the block J, the track relay T is deenergized and puts the signal S to stop. As soon as the rear end of the train has entirely left the block I, the track relay T will again pick up, and under this condition the winding I of the signal S will be energized by current of negative polarity through the following circuit:beginning at the negative terminal of the battery 29 wire 53 back contact M of the relay SR wire 42 contacts l5 -l I wire 43 contacts I3 lll wires TN and 28, front contact 29 "of the track relay T, wire '38, winding I of the signal S, wires 3|, 32, C, 32 and 33 to the midpoint of the battery 20 Since the relay SR is still deenergized and its contact 45 isstill closed the lamp L is still lighted and a yellow caution signal is displayed. A moment later, how ever, this picking up of track relay T causes its contact to pick up the relay SR through a pickup circuit including contacts H and 12 to the left (see Fig. 3) after which thesecontacts II and I2 are shunted by front contact 36 of relay SR. This picking up of relay SR extinguis'nes the lamp L, leaving the signal S dark until a second train approaches, As soon as the train in question entirely leaves'th'e block J the track relay T will reclose-its contacts22 and 29 as a result of which the stick relay SR is again picked up through the following circuit (the signal S now assuming its caution position) :beginning at the positive terminal of the battery 2B wire 21 front contact 22 of the track relay T ,wires 2 3 and 24 winding of the relay SR wires 25 and 26 contacts I4 'I ll, wire 43 contacts I3 l0 wires 2l1 and 28, front contact 29 of the track relay T, wire 30, winding I of the signal S, wires 3|, 32, C, 32 and 33 back to the midpoint of the battery 20 Also, as the train passes entirely out of theblock J (resulting in returning of the signal S to the caution position and the movement of contacts II and l2 to the left, and in energization of relay SR current from the positive terminal 2| of battery20 may flow' to the winding I of relay S. This flow of current causes the spectacle of signal S to. move to the clear position, but instead of displaying a green signal adark signalis displayed, because the open contact 45 of relay-SR keeps the lamp L deenergized. As the train in question passes out of the next block in advance of the block J, the polarity of the current flow in the'wlnding l of the signal S will be changed from negative to-positive, so that the signal S will change from caution to clear (see Figs'.,,2 and 3),; but this rapid change of the signal SXfrom-caution to clear will not in any way disturb the energizing circuit for the winding of signal S, this because the auxiliary circuitvincludeswthe stick contact 36 ofnthe relay SR Also, although the stick relay SR maybe momentarily shunted, this momentaryshunt will notv result in, dropping of the stick-relay'sR M odificatton Fig. 5 v The present invention, as-illustrated in Fig. '5, has been shown applied. to a three-aspect color light signal, in which three separate signal lamps colored green, yellow and red, respectively; have. been designated by the letters G, Y and R, and this color light signal S is controlled through the medium of theneutral contact 5| and polar contact 52 of the polar-neutral relay LR in the usual manner well understood bythoseskilledinthe art, the common wire for these lamps G,Y andR being carried through the back contact 45 in exactly the same way as is true of the lamp L of the signal S (see .Fig. 1). Since the polar neutral relay LR is controlled in exactly the same manner as is the winding 7 of the signal S, like circuit wires and contacts have been designated.

with like reference characters. having distinctive exponents 2. Also; since the operation of they system shown in Fig. 5, is exactly the same as that shown in Fig. 1 it will beunnecessary to specifically describe the same. should. be noted that the neutral contact I& I l of relay LR, engages contacts 13 -45 under deenergizedcondition of this relay, the same as contacts Ill and H of signalv S engage contacts l3 and, I5, and; that during the energized condition of relay LR the contact lip-H of relay LR, engages contacts I2. l l the same ascontacts II] or II engage, respectively, contacts l2 or l4, and the, circuits equivalents.

' Modification Fig. 6

Referring toFig. 5, if desired, instead of using a:-stick;relay SR a slow acting non-stick relay SL may be used, as shown in Fig. 6. It will be noted thatthe stick contact3li hasbeen omitted. 'With thestick contact 362 omitted the relay SL Will becontrolled directly by the contact |l l"| of the relay LR, so that'the contact 2-2 (see Fig. 5) of track relay T may also be'omitted Polechanging ofgthecircuit for the line relay.v LRwillre'sult inimomentary'dropping of the contact |0 'H but, since, the relay SL is slowdropping, current of negative polarity will notbe applied through itsback contact 4l ito the next line relay in the rear and no kick-off; williresult.

Havingythus shownand described several'specific embodiments of the presentinvention it' is desired to be understood that'the specific circuit arrangements and structures illustrated, have notb een selected for the purpose ofv showing the scope of-.the invention nor the exact construction pref-- erably employed in practicing the same, but thatthe structure has been selected for the purpose vof disclosing; the nature ofthe-invention and the manner, inwhich it may be employed in practice, and it is; desired to be understood that various changes, modifications and additions may be made, to adapt: the invention to'the particular problem encountered in practicing thesame; all without departingfrom the spirit or scope of the invention or the idea of. meansunderlying thesame, except. as demanded by. the scope of the followingclaims; v

, whatrI claim asxnew -is In this connection it completed are in each case,

1,1.v Inna railway signaling systern of the-direct current polar type; the combination with three condition signals: atea-chof a plurality of points alongthe track; of a three condition polarity responsive. device for each signal; two circuits for each polarity responsive device one energized by current ofcne polarity and the-other energized bycrrrrentvof another polarity and each including contacts ofuthe next polarity responsive de vice: in: advance; and' an auxiliary'circuit for each polarity responsive device including asource of current, a front contact of a stick relay and a front contact. ofa track relay of a track section associated with the next signal in advance.

2. In a. railway signaling system of" the direct current polar type, thecombination with three} condition. signals at each of ap'lurality of points along the track, of a three; condition: polari'tyqresponsive device for eachsignal, two circuits for each. polarity responsive device one energized by current of one polarity and the other energized by current of another polarity and-eachincluding contactsofthe-next polarity responsive device inadvance an auxiliary circuit for each polarityresponsive device including a front contact of a 2 stick relay-and a front contact of a track" relay ofa track section associated with the next signal in advance, and-means for picking up said stick relay: upon completion of one of said twocircuits;

' 3-; Ina railway signaling system of the direct current polar typeg-thecombination with a three condition signal at each'of a plurality of points along the track, of a three condition; polarity re;

sponsive device for each signal, 13W0Cl1Cl1ltS"f0I each polarity responsive device one'energize'd by rent polartype comprising, a track divided by" insulating joints'into' blocks, a track relay for each block, a three condition polarity responsive device for each block, a clear circuit for each polarity'responsive device including'in series'fr'ont" contacts of the track'relays of its block and the. next block in advance and contacts of the po'-' larity responsive device next in advance, a caution circuitfor eachpolarity responsive device including in series contacts of the track relay of the block in advance and contacts offlthe next' device in advance, a stick polarity responsive relay, a front contact of said relay in multiple withsaidcontacts of said polarity responsive device next inadvance, and meansfor picking up said stick relay upon completion of said clear circuit.

5. A railway-signaling system of thedirect cur-' rent polar type-comprising, a track divided by in jsulating joints into blocks, 7 block, athree condition polarity-responsive device for eacl'isignal, a clear circuit for-each polarity'responsivedevice including in series front contacts of the track relays of its block and'thenext'block in advance and contacts of" the polarity'respon'e sive device next inadvance, a caution circuit for each polarityresponsive device includingin series contacts of thetrack relay'of the'blockin'advance andicontacts of 'the next polarity "responsive" de- 7 with said contacts of the next" atrack: relay for eachdin ; 110. 1} railway signaling system of tliedire ct,

vice in advance, a relay included in series'in said clear circuit, and. a front-contact of said relay in multiple with the contacts of .the polarity responsive device included in said clear circuit.

6. .A railway signaling system of the direct current polar type comprising, a track divided by insulating joints into blocks, a track relay for each block, a three condition polarity responsive device for each signal, a clear circuit for eachpolarity responsive device including in series front contacts of the track relays of its block-and. the next block in advance and contacts of the polarity responsive device next in advance, a caution cir-' cuit for each polarity responsive device including in series contacts of the track relay of the block in advance and contacts of the next. polarity responsive device in advance, -a stick relay picked up upon completion of said clear circuit, and a front contact of said stick relay in multiple with the contacts ofthe polarity responsive device included in said clear circuit. V '7. A railway signaling system of the direct current polar type comprising, a track divided by insulating joints into blocks, a track relay for each block, a three condition polarity responsive device for each signal, a clear circuit for each polarity responsive device including in series front contacts of the track relays of its block and the next block in advance and contacts of the polarity responsive device next in advance, a caution circuit for each polarity responsive device including'in series contacts of the trackrelay of the block in advance and contacts of the next po-. larity responsive device in advance, a stick relay picked up upon completionof said clear circuit, a front contact of said stick relay in multiple with the contacts of the polarity responsive device ineluded in said clear circuit, and an illuminating lamp for eachsignal having an energizingcircuit including a back contact of; theassociatedstick rel y. 7

8. A railway signaling system of the direct current polar type .comprising a track divided by insulating joints intoblocks, a track relay for each block, a three condition polarity responsive device for each signal, a clear circuit 'for'each polarity responsive device including in series front.

contacts of thetrack relays of its block and the next block in advance-andcontacts of the polar:-

ity responsive device next in advance, a caution circuit for each polarity responsivedevice in-.

eluding in series contacts of the trackrelay of the blockin advance and contacts of the next polarity responsive device in -advance, a stick, 7 relay included in said clear circuit, and a; stick contact of saidrelay in multiple with the'con' tacts of the polarity responsive device included in s'aid clear. circuit, whereby thepolarity responsive device next in advance must have its' contacts closed to pick up its associated stick relay but the clear circuiti will notbe broken:

upon opening of such contacts. v V

'9'. A railway signaling system of the direct current polar type comprising, a signal of the quick acting three-position. search light type having two'. position clear contacts closed-when in itsclear position and two position caution contacts closed when in its caution positiQ l, a clear cir-' cuitfor each signal including a front clear'c'ontact or a front caution contact of the next signal injadvance, a stick relay associated with each signal, and a caution circuit for'each signal. in--. cluding a back contact of the stick relay .asso

ciated with 'the next signal in advance, 3

current polar type comprising, a signal of the quick acting three-position search light type having two position clear contacts lifted when in its clear-position and'two position caution contacts lifted when in its caution position, a clear circuitfor each'signal including either a front clear contact or a front caution contact of the next signal'in advance,'a stick relay associated with each signal, a caution circuit for each signal including a back contact of the stick relay associated with the next signal-in advance, and a front contact of each of said stick relays for shunting the clear contact and the caution contact of itsassociated signal.

11. A railway signaling system of the direct cur-rent polar type comprising, a signal of the quick acting three-position search light type having two position clear contacts lifted when in its clear position and two position caution contacts lifted when in its caution position, a clear circuit for each-signal including a front clear contact or a front caution contact of the next signal in advance, a stick relay associated with each signal having its Winding included in series in the clear circuit of the next signal in the rear, and a front contact of each stick relay shunting the clear contact and the caution contact of its associated signal.

12, A signalsystem of the type described, comprising, in combination, a three unit light signal at each of a plurality of signal locations along the'track, a polar relay for each signal for controlling the same, a control circuit for each polar relay including a contact of the next polar relay in advance and the winding of another relay located near said next polar relay' in advance, and a'front contact on said another relay for shunting said contact of the next polar relay in advance. i

13..In a railway signaling system of the direct current polar type; the combination with three condition signals at each of a plurality of points along the track; of a three condition polarity responsive device for each signal; alamp for each signal; two circuits for each polarity responsive device one energized by current of one polarity and the other energized by current of another polarity and each including contacts of the next polarity responsive device in advance; an auxiliary circuit for eachpolarity responsive device including a source of current, a front contact of a stick relay and a front contact of a track relay of a track section associated with the next signal in advance; and an energizing circuit for said lampincluding a back contact of said stick relay.

1%. A railway signaling system of the direct current polartype comprising, a signal of the quick acting three-position search light type in-' cluding a lamp and having two-position clear contactslifted when. in its clear position and two-positioncaution contacts lifted when in its caution position, a clear circuit for each signal including either a front clear contact or a front caution contact of the next signal in advance, a' stick relay associated'with each signal, a caution circuit for each signal including a back contact of the stick relay associated with the next signal in advance, a front contact of each of said stick relays for shunting the clear contact and the caution contact of its associated signal, and a back-contact of said stick relay for controlling energization of said lamp.

15. A railway signaling system of the direct current polar type comprising, a signal of the' quick acting three-position search light type including an electric lamp and having two-position clear contacts lifted when in its clear position and two-position caution contacts lifted when in its caution position, a clear circuit for each signal including a front clear contact or a front caution contact of the next signal in advance, a stick relay associated with each signal having its winding included in series in the clear circuit of the next signal in the rear, a front contact of each stick relay shunting the clear contact and the caution contact of its associated signal, and. a back contact of said stick relay for controlling energization of said lamp.

16. A signal system of the type described, comprising in combination, a multiple unit light signal at each of a plurality of signal locations along the track, a polar relay for each signal for controlling the same, a control circuit for each polar relay including a contact of the next polar relay irr advance and the winding of another relay located near said next polar relay in advance, a front contact on said another relay for shunting said contact of the next polar relay in advance,

and a back contact of said another relay included in series with a common wire leading to the light signal units of said multiple unit light signal.

17. In .a signal system of the character described; comprising in combination a signal at the entrance to each of a plurality of blocks; a polar relay for each signal; another relay for each signal; a clear circuit for each polar relay including in series front contacts of said polar relay at the next signal in advance, the winding of said another relay for the next signal in advance and a contact closed only if the second block in advance is unoccupied, and a shunt relay.

branch circuit for said front contacts of such polar relay including a front contact of the associated another relay.

18. In a signal system of the character described; comprising in combination a signal at the entrance to each of a plurality of blocks; a

polar relay for each signal; another relay for I each signal; a clear circuit for each polar relay including in series front contacts of said polar relay at the next signal in advance, the winding of said another relay for the next signal in advance and a contact closed only if the second block in advance is unoccupied; a shunt branch circuit for said front contacts of such polar relay including a front contact of the associated another relay; and a caution circuit for each polar relay including a back contact of the polar relay and Ya back contact of the another relay for the signal next in advance.

19. In a signal system of the character described; comprising in combination a signal at the entrance to each of a plurality of blocks; a polar relay for each signal; another relay for each signal; a clear circuit for each polar relay including in series front contacts of said. polar relay at the next signal in advance, the winding of said another relay for the next signal in advance and a contact closed only if the second block in advance is unoccupied; a shunt branch circuit for said front contacts of such polar relay including a front contact of the, associated another relay; and an illuminating circuit for each signal including a back contact of its associated another JERRY BENNETT. 

